1. Field of the Invention
The present invention relates to technologies that output images based on image data, and, in particular, relates to inventions that output images by generating an appropriate density of dots through performing specific image processing on image data.
2. Description of the Related Art
Image output devices for outputting images by forming dots on various types of output media such as printed media or liquid crystal displays, are widely known as output devices for various types of imaging devices. In these image output devices, the images are handled in a form where they are finely divided into minute regions known as pixels, and dots are formed in these pixels. When dots are formed in pixels, examining the individual pixels, of course, will reveal only the state of whether or not dots are formed. However, viewing an adequately broad region can cause the dots that have been formed to appear as a rough tone density, making it possible to output a multitone image through changing the density of the dots that are formed. For example, when forming dots from black ink on printing paper, regions wherein the dots are formed densely will appear to be dark, and, conversely regions wherein the dots are sparse will appear to be light. Consequently, controlling appropriately the density with which the dots are formed enables the outputting of multitone images. The data for controlling the formation of dots so as to be able to obtain the appropriate dot creation density in this way is produced through executing specific image processing on the images to be outputted.
Recent years have seen a demand for larger and higher quality outputted images in these image outputting devices. Splitting the images into finer pixels is effective in responding to the demands for high quality images. Making the pixels smaller enables an increase in the image quality because the dots that make up the images become indiscernible, and thus produce higher image quality. Conversely, the demands for larger images are handled by increasing the number of pixels. While, of course, the output images can be made larger by enlarging the individual pixels, doing so would lead to a reduction in the image quality, so increasing the number of pixels is an effective response to the demand for larger images.
Naturally, when the number of pixels comprising the image is increased, more time is required for image processing, making it difficult to output the images quickly. Given this, a technology able to perform imaging processing quickly has been proposed. (Japanese Unexamined Patent Application Publication 2002-185789)
However, even if the image processing is performed quickly, time is required for transferring the original image data, and for transferring again the image data after processing has been completed, and thus there are also limits on the effect of the aforementioned technology on speeding up the outputting of the images.
Moreover, in recent years there have been demands by those who wish to directly output images by supplying image data taken from, for example, digital cameras, directly to image output devices such as printing devices. In such cases, performing image processing using image processing devices equipped with high levels of processing capabilities, such as in so-called personal computers, is not possible. Consequently, image processing must be simple, such as can be performed on the image capture device, such as a digital camera, or on the image output device, or jointly between the two.
The present invention was created in order to solve the problem described above in the conventional technology, and the object thereof is to provide a simple image processing technology wherein image processing and data transfer can be performed at high speeds, while maintaining an adequate output image quality.